The present invention relates to stranding cable elements of large cross sections, such as conductor elements, each of which being comprised of multiple, stranded filaments, leads, or wires.
In U.S. Pat. No. 4,311,002 (CIP of Ser. No. 944,582), a stranding machine and method has been proposed as follows. A plurality of stationarily mounted but reelable support spools store individual strand elements to be unwound from the spools and combined in a first, nonrotating stranding point. A capstan structure is disposed upstream from that first stranding point and grips the bundle, holds it for a certain travel and storage path, and releases it again, all the while rotating about an axis in the travel path to, thereby, strand or twist the elements about each other and between the stationary stranding point and the point of gripping. Any (additional) twist is not imparted upon the bundle while it is held by and stored in the capstan. A second stranding point is defined and established downstream from the capstan so that the bundle while traveling from the release point of the capstan to the second stranding point receives an additional twist.
The method and equipment as described in said patent is quite advantageous from a point of view of stranding large-diameter stranding elements. It was found, however, that stranding elements of large diameters and being themselves of a stranded construction may exhibit such a degree of flexibility (lack of stiffness) that their position in the stranded bundle as it is being made is not always well defined.
The subject matter added to the continuation application of the above-mentioned patent deals specifically with one aspect of stranding large-diameter elements. The problem solved there related specifically to the stranding zone as between the capstan and the second stranding point and solved a problem arising particularly if the stranding machine is operated to obtain the so-called SZ-stranding pattern.